| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polyester film for a solar battery backside protective film, which allows suppression of deterioration of mechanical properties owing to extended time of use in hot and humid surroundings. <P>SOLUTION: The polyester film for a solar battery backside protective film includes: a white polyester film layer made of a polyester composition of 85-96 wt.% of polyethylene terephthalate, which results from a polymerization using antimony compound and/or titanium compound as a polycondensation catalyst, and 4-15 wt.% of rutile type titanium oxide particles. The polyester composition includes 10-40 mmol% of a certain phosphoric acid compound and a total of 2-50 mmol% of antimony and/or titanium in terms of metal element based on the molar number of the whole dicarboxylic acid component constituting the polyethylene terephthalate. In the polyester film for a solar battery backside protective film, before and after aging at a temperature of 85°C and a humidity of 85%RH for 3000 hours, the retention of elongation is 50% or larger, and the delamination strength is 6 N/15 mm or larger. <P>COPYRIGHT: (C)2012,JPO&INPIT |
